THERMOGRAPHIC DETECTION OF CONDUCTING CONTAMINANTS IN
|
|
- Felicia Doyle
- 5 years ago
- Views:
Transcription
1 THERMOGRAPHIC DETECTION OF CONDUCTING CONTAMINANTS IN COMPOSITE MATERIALS USING MICROWAVE EXCITATION M.W. Bowen Lockheed Aeronautical Systems Company Marietta, GA R. Osiander, J.W.M. Spicer and J.e. Murphy The Johns Hopkins University Applied Physics Laboratory Laurel, MD INTRODUCTION This paper describes microwave-source time-resolved infrared radiometry (MW -TRIR) as a method for the detection and characterization of microwave absorption by conductive fibers and other absorbing regions in dielectric materials. Due to recent technical developments in the speed, detector array size, and sensitivity of infrared focalplane arrays, time-resolved infrared radiometry has evolved into an important NDE tool which allows fast area inspection at high spatial resolution. While much prior work has focused on the detection of structural defects or disbonds in a variety of materials [1,2], the increasing importance of composite materials requires new approaches to inspection which allow characterization of local material properties. Defects in such materials may have little thermal contrast compared to the matrix material and may be invisible using conventional infrared radiometry methods. However, where the embedding material is a weak microwave absorber, localized microwave absorbing regions can be detected easily. There are three different classes of absorption processes: (1) dielectric loss (e.g. water), (2) magnetic loss, and (3) Joule heating (e.g. electromagnetic radiation interaction with conducting fibers). An example of Process (1) has been the use of time-resolved infrared radiometry (TRIR) with a microwave heating source to detect water in composite materials [3,4]. The other two processes, magnetic loss and Joule heating, have been used for microwave field imaging [5,6,7]. In a thin absorbing sample the heating pattern is related and, in some experimental conditions, is proportional to the microwave energy distribution on the surface. A thin epoxy sheet loaded with ferrite can be used as an example of a magnetic absorber and any thin metallic or carbon layer with given surface conductivity can be used to show the electric field distribution through Joule heating. When the size of the microwave absorbing region becomes smaller than the microwave wavelength (about 1" for X-Band (8-12 GHz», the heating pattern is determined by the defect geometry. In the case of a conductor, discontinuities such as an edge heat up more than the rest of the defect. As a result, small, conducting, one-dimensional structures such as metal wires or fibers are very efficient microwave absorbers. Such small absorbing structures cannot be imaged with a resolution better than about one wavelength with a microwave imaging system such as a radar range due to the Rayleigh criterium. The thermographic imaging technique allows much higher resolutions since the limiting spatial resolution of the infrared detector given by the Rayleigh criterium is about m. Review of Progress in Quantitative Nondestructive Evaluation. Vol. 14 Edited by D.O. Thompson and D.E. Chimenti, Plenum Press, New York,
2 Such small linear conducting defects can occur in a composite fabrication environment. The quality of the composite structures depends on the purity of the different layers and is an important factor for applications in the aerospace industry. Thermographic detection with microwave excitation is a method which can detect and identify these defects. With its timeresolved aspect, TRIR [8] allows the defect depth to be determined. This can be used for evaluation of potential repairs, because defects close to the surface could be removed with minor impact on the structure. EXPERIMENTAL SETUP Figure 1 shows a diagram of the experimental setup. All the measurements described here use an HP 6890B Oscillator (5-10 GHz) to produce microwaves at a frequency of 9 GHz. This signal is amplified to a maximum power of 2.3 W by a Hughes 1277 X-band traveling wave tube amplifier and fed into a single flare horn antenna through rectangular waveguide. The antenna has a beam width of about 50 degrees and is placed about 15 cm from the sample. Both the angle of incidence and the polarization of the microwave field relative to the sample are controlled. In addition, the specimen is mounted on an X-Y-Z stage to allow accurate control of sample position. A 128x128 InSb focalplane array (Santa Barbara Focalplane) operating in the 3-5 J.!m band is used for detection of the IR radiation. The camera has a temperature resolution of about 3 mk and a frame rate as fast as 305 Hz or 3.3 ms per frame. The frame synchronization pulse of the infrared camera triggers the microwave oscillator and the sample temperature is monitored as a function of time during the microwave pulse. This allows longer observation times with low power input and hence small temperature rises, as in time resolved infrared radiometry with optical heating. Time-dependent measurements are made by recording a series of frames before, during and after the application of the microwave step heating pulse. The total measurement time is easily varied by selecting the appropriate frame rate, the number of frames to be recorded and the number of skipped frames between each recorded frame. These frames are stored in a buffer board in the microcomputer which controls the focalplane array camera and are subsequently stored on Bernouilli disks for analysis. Analysis of these buffer files is performed using LabVIEW routines on a Macintosh Quadra 840A V computer which allows a range of information to be extracted from the data. Trigger M\'I-Generator o TWT-Amp. M\'I-Horn. Sample Panel Microcomputer MW-Absorber Fig oj '".., Experimental setup for microwave-trir measurements. 454
3 EXPERIMENTAL RESULTS Experiments to study the interaction of microwaves with linear conductors were performed on carbon fibers in different epoxy structures. The electromagnetic interaction depends on fiber length, thickness, and microwave polarization. The thermal response depends on the depth of the fiber in the structure and on the thermal properties of the embedding material. One advantage of infrared radiometry for detection is that a spatial resolution much better than the microwave wavelength can be obtained. Figure 2 shows an image reconstructed from a microwave hologram of a fiberglass-epoxy specimen with embedded fibers at different locations. The microwave hologram is produced from the magnitude and phase angle of the reflected microwaves when scanning an emitting and a receiving hom in a plane. The image of the reflection distribution is reconstructed digitally from this hologram. The fibers can be detected in this image and although the response depends on fiber size and orientation, these parameters cannot be imaged directly. The spatial resolution in this measurement is given by the Rayleigh criterium at the microwave wavelength. The thermal detection method, as shown in the experiments below, is sensitive to orientation, length, and its spatial resolution is limited just by the optical parameters. Dependence on Fiber D\4>th A schematic diagram showing the coordinate system used for the analytical description is shown in Fig. 3. A line source, buried at a depth z, is heated uniformly. The response measured by the IR camera is proportional to the surface temperature T(x,y,z=O). For a semiinfinite medium the solution of the thermal diffusion equation for an infinite line source with continuous heating is given by [9]: (1) Fig. 2 Image of the reflected microwave power, reconstructed from a microwave hologram of fiberglass-epoxy specimen with embedded fibers of different lengths and orientations. 455
4 where Ei(x) is the exponential integral and a is the thermal diffusivity. This expression can be used to fit both the time dependence and the spatial dependence of the temperature distribution to get a value for (x2+y2)/a. The thermal response of the heated fiber depends on the depth of the fiber and on the thermal properties of the embedding material. Figure 4 shows an infrared image of a carbon fiber in fiberglass-epoxy after 8 s heating. The time dependence of the temperature at the center of the fiber, taken from successive images, is shown for both fibers in Fig. 5. The solid line was calculated with Eq. 1, assuming an infinite line heating source at a given depth. Fitting Eq. 1 onto the experimental result yields a value of cm2/s for the thermal diffusivity, knowing the depth of the fibers was 0.25 mm and 0.75 mrn. The spatial distribution of the temperature across the fibers was calculated with these values and Eq. (1). This is shown in Fig. 6 together with the experimental results for different times and the two different fiber depths. The agreement is very good. An application similar to the detection of conducting fibers in dielectric materials is shown in Fig. 7. It shows the IR images of microwave absorbing foam containing metal slivers. The slivers show up after 10 s of heating in the IR image since they are heated more than the foam. Fig. 3 Schematic diagram of coordinate system used for analytical development. Fig. 4 Infrared image of fiberglass-epoxy composite with carbon fiber contaminate after an 8 s microwave heating pulse. 456
5 () 0.75 mm IJ mm 1000 to) ;::j... to) e to) E-< Fig Squareroot (time [mk]) Surface temperature as a function of square root time for a single point on fibers in 0.25 mm and 0.75 mm depth. Solid lines are calculated with Eq. 1. SZ E d=o.25 mm, 3.9 s --d=o.75 mm, 3.9 s 1200 d=o.25 mm, 2.6 mm, ::J Cii a. E 400 r d=o.25 mm, 1.3,. mm, 1.3 s Position [em] Fig. 6 Temperature distribution across each of the fibers of Fig
6 Dependence on Fiber Orientation The microwave absorption is very sensitive to the polarization of the electric field with respect to the fiber direction. For thin fibers only the electic field component along the fiber direction (E cos e ) can induce a current in the fiber. The polarization of the microwaves can be changed by rotating the horn and measurements were made with steps of 15 deg in the polarization angle. The temperature rise at one point on the sample is plotted in Fig. 8 as a function of the angle of polarization with respect to the fiber direction and shows the expected cosine behavior. After Cut Sliver insened OK..., == l. B K Fig. 7 IR image of microwave absorbing foam after los microwave illumination with and without a metal sliver inserted SZ' 300 E. ::J 250 Cil... a. E 200 I-..l<: C\l 150 a Angle of Polarization [deg] Fig. 8 Temperature at fiber center as a function of polarization angle. 458
7 De.pendence on Fiber Length The interaction is strongly dependent on the length of the fiber. Figure 9 shows a series of IR images for carbon fibers of different lengths in fiberglass-epoxy. In Fig. 10 the temperature distribution along each fiber is plotted for different fiber lengths. Note that for fibers longer than 12 mm the temperature shows a modal distribution along the fiber. Fig. 9 IR images for different fiber lengths. sz 1000 E- O) en a: :l 0) a. E 0) I B--6mm --a mm -+-12mm 18 mm -+-24mm -----tr- 30 mm o o Position [em] Fig. 10 Temperature distribution along fiber axis for different fiber lengths. 459
8 CONCLUSIONS We have shown that time-resolved infrared radiometry is a very useful tool in NDE for microwave absorbing materials or microwave absorbing defects. It can be used for contaminate detection as well as for homogeneity studies. The possibility of heating buried microwave absorbers directly gives a very high contrast for such defects. Further it allows the use of deliberately implanted "defects" to be used as sensors to provide information about the material using the TRIR approach. This can be used to monitor curing of epoxy materials, deterioration of materials, or other processes such as thickness changes during coating deposition. REFERENCES 1 J.W. Maclachlan Spicer, W.D. Kerns, L.e. Aamodt and J.C. Murphy, 1. Nondestruc. Eval. 8 (2) p. 107 (1989). 2 J. W. M. Spicer, W. D. Kerns, L. e. Aamodt, J. e. Murphy, in Review of Progress in Quantitative Nondestructive Evaluation, Vol 11, pp , edited by D. O. Thompson and D. E. Chimenti, Plenum Press, New York (1992). 3 R. Osiander, 1. W. M. Spicer, 1. e. Murphy, in Thermosense XVI, edited by J.R. Snell, Jr., SPIE 2245, pp (1994). 4 R Osiander, 1. W. M. Spicer, and 1. C. Murphy, to be published in Proceedings of the 8th International Topical Meeting on Photoacoustic & Photothermal Phenomena, Journal de Physique - Colloques (1994). 5 J.D. Norgard, J. Sadler, RM. Sega, E.A. Baca, and W. Prather, in Thermosense XVI, edited by J.R Snell, Jr., SPIE 2245, pp (1994). 6 M.R. Seiler, 1.L. Haselwood, and L.A. Stockum, in Thermosense XIV, edited by J.K. Eklund, Proc. SPIE 1682, pp (1992). 7 D.L. Balageas, P. Levesque, and A. Deom, in Thermosense XV, edited by J.K. Eklund, Proc. SPIE 1933, pp (1992). 8 L.C. Aamodt, J.W. Maclachlan Spicer and J.e. Murphy, 1. Appl. Phys. 68 (12) p (1990). 9 H.S. Carslaw and 1.e. Jaeger, Conduction of Heat in Solids (Oxford Univ. Press, London 1959). 460
MICROWAVE SCATTERING FOR THE CHARACTERIZATION OF A DISC-SHAPE VOID IN DIELECTRIC MATERIALS AND COMPOSITES
MICROWAVE SCATTERING FOR THE CHARACTERIZATION OF A DISC-SHAPE VOID IN DIELECTRIC MATERIALS AND COMPOSITES John M. Liu Code 684 Naval Surface Warfare Center Carderock Div. West Bethesda, Md. 20817-5700
More informationHigh power microwave antenna design using infrared imaging techniques by NORGARD J.", SADLER J. 0, BACA E. 0, PRATHER W. SEGA R. + and SEIFERT R.... US Air Force Academy & University of Colorado, Colorado
More informationTiré à Part. Single-sided interferometric EMIR method for NDE of structures. P. Levesque, D. Balageas
Tiré à Part Single-sided interferometric EMIR method for NDE of structures P. Levesque, D. Balageas QIRT'98 Eurotherma Seminar 60 Lodz (Pologne), September 07-10, 1998 TP 2003-14 Single-sided interferometric
More informationMicrowaves holography revealed by photothermal films and lock-in IR thermography: Application to electromagnetic materials NDE
Microwaves holography revealed by photothermal films and lock-in IR thermography: Application to electromagnetic materials NDE Daniel L. Balageas, Patrick Levesque, Mylène Nacitas, Jean-Claude Krapez,
More informationSynchronized electronic shutter system (SESS) for thermal nondestructive evaluation Joseph N. Zalameda
Header for SPIE use Synchronized electronic shutter system (SESS) for thermal nondestructive evaluation Joseph N. Zalameda U. S. Army Research Laboratory, Vehicle Technology Directorate Nondestructive
More informationMICROWAVE SUB-SURFACE IMAGING TECHNOLOGY FOR DAMAGE DETECTION
MICROWAVE SUB-SURFACE IMAGING TECHNOLOGY FOR DAMAGE DETECTION By Yoo Jin Kim 1, Associate Member, ASCE, Luis Jofre 2, Franco De Flaviis 3, and Maria Q. Feng 4, Associate Member, ASCE Abstract: This paper
More informationPARALLEL BOX-CAR IMAGING OF ADHESION DEFECfS IN PLASMA-SPRA YED
PARALLEL BOX-CAR IMAGING OF ADHESION DEFECfS IN PLASMA-SPRA YED COATINGS P.K. Kuo, T.Ahmed, L.D. Favro, H.J. Jin, and R.L. Thomas, Department of Physics, Wayne State University Detroit, MI 48202 J. Jaarinen
More informationEVALUATION OF MICROWAVE METHODS FOR THICKNESS MEASUREMENTS OF UQUID SHIM MATERIAL
EVALUATION OF MICROWAVE METHODS FOR THICKNESS MEASUREMENTS OF UQUID SHIM MATERIAL D.D. Palmer, S.C. Buckner and W.S. Samford McDonnell Aircraft Company McDonnell Douglas Corporation P.O. Box 516 St. Louis,
More informationL.D. Favro, H.I. Jin, T.Ahmed, X.Wang, P.K. Kuo and R.L. Thomas
INFRARED THERMAL WAVE STUDIES OF COATED SURFACES L.D. Favro, H.I. Jin, T.Ahmed, X.Wang, P.K. Kuo and R.L. Thomas Department of Physics and Institute for Manufacturing Research Wayne State University Detroit,
More informationNoise generators. Spatial Combining of Multiple Microwave Noise Radiators NOISE ARRAY. This article reports on. experiments to increase the
From April 2008 High Frequency Electronics Copyright 2008 Summit Technical Media LLC Spatial Combining of Multiple Microwave Noise Radiators By Jiri Polivka Spacek Labs Inc. Noise generators This article
More informationEFFECT OF SURFACE COATINGS ON GENERATION OF LASER BASED ULTRASOUND
EFFECT OF SURFACE COATINGS ON GENERATION OF LASER BASED ULTRASOUND V.V. Shah, K. Balasubramaniam and J.P. Singh+ Department of Aerospace Engineering and Mechanics +Diagnostic Instrumentation and Analysis
More informationEVOLUTION OF THE CRYOGENIC EDDY CURRENT MICROPROBE
EVOLUTION OF THE CRYOGENIC EDDY CURRENT MICROPROBE J.L. Fisher, S.N. Rowland, J.S. Stolte, and Keith S. Pickens Southwest Research Institute 6220 Culebra Road San Antonio, TX 78228-0510 INTRODUCTION In
More informationMicrowave Testing (µt): An Overview. Johann Hinken, FI Test- und Messtechnik GmbH Magdeburg, Germany, July 2016
Microwave Testing (µt): An Overview Johann Hinken, FI Test- und Messtechnik GmbH Magdeburg, Germany, July 2016 More info about this article: http://www.ndt.net/?id=21377 Content: 1. Introduction 2. Physical
More informationLASER GENERATION AND DETECTION OF SURFACE ACOUSTIC WAVES
LASER GENERATION AND DETECTION OF SURFACE ACOUSTIC WAVES USING GAS-COUPLED LASER ACOUSTIC DETECTION INTRODUCTION Yuqiao Yang, James N. Caron, and James B. Mehl Department of Physics and Astronomy University
More informationEFFECTS OF LIFT-OFF ON MICROWAVE NDE USING AN OPEN-ENDED RECTANGULAR WAVEGUIDE
EFFECTS OF LIFT-OFF ON MICROWAVE NDE USING AN OPEN-ENDED RECTANGULAR WAVEGUIDE John M. Liu Code 684 Carderock Div. Naval Surface Warfare Ctr. Silver Spring, Md. 20903-5640 M. Allen Matteson Code 615 Carderock
More informationMicro-sensors - what happens when you make "classical" devices "small": MEMS devices and integrated bolometric IR detectors
Micro-sensors - what happens when you make "classical" devices "small": MEMS devices and integrated bolometric IR detectors Dean P. Neikirk 1 MURI bio-ir sensors kick-off 6/16/98 Where are the targets
More informationAIR-GAP DETECTION IN DIELECTRIC MATERIALS BY A STEP-FREQUENCY MICROWAVE TECHNIQUE
AR-GAP DETECTON N DELECTRC MATERALS BY A STEP-FREQUENCY MCROWAVE TECHNQUE John M. Liu Code 684 Carderock Division, White Oak Det. Naval Surface Warfare Center Silver Spring, Md. 20903-5640 NTRODUCTON Most
More informationInvestigation of Woven Fiber Reinforced Laminated Composites Using a Through Transmission Ultrasonic Technique
Photos placed in horizontal position with even amount of white space between photos and header Photos placed in horizontal position with even amount of white space between photos and header Investigation
More informationThe on-line detection of moisture and coatings by means of thermal waves. by R. Huttner and E. Schollmeyer
The on-line detection of moisture and coatings by means of thermal waves moist by R. Huttner and E. Schollmeyer Oeutsches Texfilforschungszentrum Nord-West e. V., Institut an der Universitat Ouisburg Gesamthochschule,
More informationDepth profiling of orientation in laminates with local lockin thermography by KARPEN W., WU D., STEEGMOLLER R., and BUSSE G.* * Institut far KunststoffprOfung und Kunststoffkunde (IKP), Universitlit Stuttgart,
More informationTHE ANALYSIS OF ADHESIVE BONDS USING ELECfROMAGNETIC
THE ANALYSIS OF ADHESIVE BONDS USING ELECfROMAGNETIC ACOUSTIC TRANSDUCERS S.Dixon, C.Edwards, S.B.Palmer Dept of Physics University of Warwick Coventry CV 4 7 AL INTRODUCfION EMATs have been used in ultrasonic
More informationMICROWAVE THICKNESS MEASUREMENTS OF MAGNETIC COATINGS. D.D. Palmer and V.R. Ditton
MICROWAVE THICKNESS MEASUREMENTS OF MAGNETIC COATINGS D.D. Palmer and V.R. Ditton McDonnell Aircraft Company McDonnell Douglas Corporation P.O. Box 516 St. Louis, MO 63166 INTRODUCTION Microwave nondestructive
More informationA NOVEL NEAR-FIELD MILLIMETER WAVE NONDESTRUCTIVE INSPECTION TECHNIQUE FOR DETECTING AND EVALUATING ANOMALIES IN POLYMER JOINTS
ICONIC 2007 St. Louis, MO, USA June 27-29, 2007 A NOVEL NEAR-FIELD MILLIMETER WAVE NONDESTRUCTIVE INSPECTION TECHNIQUE FOR DETECTING AND EVALUATING ANOMALIES IN POLYMER JOINTS Sergey Kharkovsky 1, Emilio
More informationEmerging NDE Technology for Aging Aircraft
Emerging NDE Technology for Aging Aircraft David G. Moore Richard L. Perry Sandia National Laboratories - Federal Aviation Administration Airworthiness Assurance NDI Validation Center Albuquerque, New
More informationFull Polarimetric THz Imaging System in Comparison with Infrared Thermography
11th European Conference on Non-Destructive Testing (ECNDT 2014), October 6-10, 2014, Prague, Czech Republic More Info at Open Access Database www.ndt.net/?id=16556 Full Polarimetric THz Imaging System
More informationCHAPTER 2 MICROSTRIP REFLECTARRAY ANTENNA AND PERFORMANCE EVALUATION
43 CHAPTER 2 MICROSTRIP REFLECTARRAY ANTENNA AND PERFORMANCE EVALUATION 2.1 INTRODUCTION This work begins with design of reflectarrays with conventional patches as unit cells for operation at Ku Band in
More informationTHE ELECTROMAGNETIC FIELD THEORY. Dr. A. Bhattacharya
1 THE ELECTROMAGNETIC FIELD THEORY Dr. A. Bhattacharya The Underlying EM Fields The development of radar as an imaging modality has been based on power and power density It is important to understand some
More informationMICROWAVE FIELD MEASUREMENT OF DELAMINATIONS IN CFRP CONCRETE MEMBERS IN A BRIDGE
MICROWAVE FIELD MEASUREMENT OF DELAMINATIONS IN CFRP CONCRETE MEMBERS IN A BRIDGE V. Stephen, S. Kharkovsky, J. Nadakuduti, R. Zoughi; Applied Microwave Nondestructive Testing Laboratory (amntl), Department
More informationSupplementary Figure S1. Schematic representation of different functionalities that could be
Supplementary Figure S1. Schematic representation of different functionalities that could be obtained using the fiber-bundle approach This schematic representation shows some example of the possible functions
More informationSTUDY ON SAW ATTENUATION OF PMMA USING LASER ULTRASONIC
STUDY ON SAW ATTENUATION OF PMMA USING LASER ULTRASONIC TECHNIQUE INTRODUCTION D. F ei, X. R. Zhang, C. M. Gan, and S. Y. Zhang Lab of Modern Acoustics and Institute of Acoustics Nanjing University, Nanjing,
More informationInduction thermography for automatic crack detection in automotive components
Induction thermography for automatic crack detection in automotive components by L. Franco*, F. Rodríguez* and J. Otero* More info about this article: http://www.ndt.net/?id=20681 Abstract * AIMEN Technology
More informationELEC4604. RF Electronics. Experiment 1
ELEC464 RF Electronics Experiment ANTENNA RADATO N PATTERNS. ntroduction The performance of RF communication systems depend critically on the radiation characteristics of the antennae it employs. These
More informationWaveguiding in PMMA photonic crystals
ROMANIAN JOURNAL OF INFORMATION SCIENCE AND TECHNOLOGY Volume 12, Number 3, 2009, 308 316 Waveguiding in PMMA photonic crystals Daniela DRAGOMAN 1, Adrian DINESCU 2, Raluca MÜLLER2, Cristian KUSKO 2, Alex.
More informationFATIGUE CRACK CHARACTERIZATION IN CONDUCTING SHEETS BY NON
FATIGUE CRACK CHARACTERIZATION IN CONDUCTING SHEETS BY NON CONTACT STIMULATION OF RESONANT MODES Buzz Wincheski, J.P. Fulton, and R. Todhunter Analytical Services and Materials 107 Research Drive Hampton,
More informationDesign and Development of Tapered Slot Vivaldi Antenna for Ultra Wideband Applications
Design and Development of Tapered Slot Vivaldi Antenna for Ultra Wideband Applications D. Madhavi #, A. Sudhakar #2 # Department of Physics, #2 Department of Electronics and Communications Engineering,
More informationFirst Observation of Stimulated Coherent Transition Radiation
SLAC 95 6913 June 1995 First Observation of Stimulated Coherent Transition Radiation Hung-chi Lihn, Pamela Kung, Chitrlada Settakorn, and Helmut Wiedemann Applied Physics Department and Stanford Linear
More informationOblique incidence measurement setup for millimeter wave EM absorbers
Oblique incidence measurement setup for millimeter wave EM absorbers Shinichiro Yamamoto a) and Kenichi Hatakeyama Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji-shi, Hyogo 671
More informationOPTICAL FIBER-BASED SENSING OF STRAIN AND TEMPERATURE
OPTICAL FIBER-BASED SENSING OF STRAIN AND TEMPERATURE AT HIGH TEMPERATURE K. A. Murphy, C. Koob, M. Miller, S. Feth, and R. O. Claus Fiber & Electro-Optics Research Center Electrical Engineering Department
More informationSensor and Simulation Notes Note 548 October 2009
Sensor and Simulation Notes Note 548 October 009 Design of a rectangular waveguide narrow-wall longitudinal-aperture array using microwave network analysis Naga R. Devarapalli, Carl E. Baum, Christos G.
More informationarxiv:physics/ v1 [physics.optics] 28 Sep 2005
Near-field enhancement and imaging in double cylindrical polariton-resonant structures: Enlarging perfect lens Pekka Alitalo, Stanislav Maslovski, and Sergei Tretyakov arxiv:physics/0509232v1 [physics.optics]
More informationNDT-PRO Services expands service offering
NDT-PRO Services expands service offering NDT-PRO Services announced the formal release of two advanced NDT methods, Phased Array (including TOFD) and Eddy Current. What are they and where are the used?
More informationPractical Considerations for Radiated Immunities Measurement using ETS-Lindgren EMC Probes
Practical Considerations for Radiated Immunities Measurement using ETS-Lindgren EMC Probes Detectors/Modulated Field ETS-Lindgren EMC probes (HI-6022/6122, HI-6005/6105, and HI-6053/6153) use diode detectors
More informationAnalysis of Crack Detection in Metallic and Non-metallic Surfaces Using FDTD Method
ECNDT 26 - We.4.3.2 Analysis of Crack Detection in Metallic and Non-metallic Surfaces Using FDTD Method Faezeh Sh.A.GHASEMI 1,2, M. S. ABRISHAMIAN 1, A. MOVAFEGHI 2 1 K. N. Toosi University of Technology,
More informationR. Schneider Fraunhofer-Institute for Nondestructive Testing Saarbriicken, Germany
MICROWAVE IMAGING OF DEFECTS IN SOLIDS K. Mayer, K. J. Langenberg Dept. Electrical Engineering University of Kassel 34109 Kassel, Germany R. Schneider Fraunhofer-Institute for Nondestructive Testing 66123
More informationA Two-Dimensional Electronically-Steerable Array Antenna for Target Detection on Ground
Purdue e-pubs Birck and NCN Publications Birck Nanotechnology Center 2011 A Two-Dimensional Electronically-Steerable Array Antenna for Target Detection on Ground Dowon Kim, kim62@purdue.edu Xiang Cui Ankith
More informationRayleigh Wave Interaction and Mode Conversion in a Delamination
Rayleigh Wave Interaction and Mode Conversion in a Delamination Sunil Kishore Chakrapani a, Vinay Dayal, a and Jamie Dunt b a Department of Aerospace Engineering & Center for NDE, Iowa State University,
More informationFrequency Tunable Low-Cost Microwave Absorber for EMI/EMC Application
Progress In Electromagnetics Research Letters, Vol. 74, 47 52, 2018 Frequency Tunable Low-Cost Microwave Absorber for EMI/EMC Application Gobinda Sen * and Santanu Das Abstract A frequency tunable multi-layer
More informationWaveguides. Metal Waveguides. Dielectric Waveguides
Waveguides Waveguides, like transmission lines, are structures used to guide electromagnetic waves from point to point. However, the fundamental characteristics of waveguide and transmission line waves
More informationDEEP FLAW DETECTION WITH GIANT MAGNETORESISTIVE (GMR) BASED SELF-NULLING PROBE
DEEP FLAW DETECTION WITH GIANT MAGNETORESISTIVE (GMR) BASED SELF-NULLING PROBE Buzz Wincheski and Min Namkung NASA Langley Research Center Hampton, VA 23681 INTRODUCTION The use of giant magnetoresistive
More informationHIGH-SPEED TIME AVERAGE DIGITAL HOLOGRAPHY FOR NDT OF CURVED SANDWICH STRUCTURES
Proceedings of the National Seminar & Exhibition on Non-Destructive Evaluation NDE 2011, December 8-10, 2011 HIGH-SPEED TIME AVERAGE DIGITAL HOLOGRAPHY FOR NDT OF CURVED SANDWICH STRUCTURES Binu P. Thomas
More information9. Microwaves. 9.1 Introduction. Safety consideration
MW 9. Microwaves 9.1 Introduction Electromagnetic waves with wavelengths of the order of 1 mm to 1 m, or equivalently, with frequencies from 0.3 GHz to 0.3 THz, are commonly known as microwaves, sometimes
More informationELECTRONIC HOLOGRAPHY AND SHEAROGRAPHY NDE FOR INSPECTION
ELECTRONIC HOLOGRAPHY AND SHEAROGRAPHY NDE FOR INSPECTION OF MODERN MATERIALS AND STRUCTURES 1. F. Clarady and M. Summers Pratt & Whitney P. O. Box 109600 MIS 707-21 West Palm Beach, FL 33410-9600 (407)
More informationMICROWAVE MICROWAVE TRAINING BENCH COMPONENT SPECIFICATIONS:
Microwave section consists of Basic Microwave Training Bench, Advance Microwave Training Bench and Microwave Communication Training System. Microwave Training System is used to study all the concepts of
More information746A27 Remote Sensing and GIS
746A27 Remote Sensing and GIS Lecture 1 Concepts of remote sensing and Basic principle of Photogrammetry Chandan Roy Guest Lecturer Department of Computer and Information Science Linköping University What
More informationImprovement of terahertz imaging with a dynamic subtraction technique
Improvement of terahertz imaging with a dynamic subtraction technique Zhiping Jiang, X. G. Xu, and X.-C. Zhang By use of dynamic subtraction it is feasible to adopt phase-sensitive detection with a CCD
More informationKULLIYYAH OF ENGINEERING
KULLIYYAH OF ENGINEERING DEPARTMENT OF ELECTRICAL & COMPUTER ENGINEERING ANTENNA AND WAVE PROPAGATION LABORATORY (ECE 4103) EXPERIMENT NO 3 RADIATION PATTERN AND GAIN CHARACTERISTICS OF THE DISH (PARABOLIC)
More informationInfrared Perfect Absorbers Fabricated by Colloidal Mask Etching of Al-Al 2 O 3 -Al Trilayers
Supporting Information Infrared Perfect Absorbers Fabricated by Colloidal Mask Etching of Al-Al 2 O 3 -Al Trilayers Thang Duy Dao 1,2,3,*, Kai Chen 1,2, Satoshi Ishii 1,2, Akihiko Ohi 1,2, Toshihide Nabatame
More informationAn acousto-electromagnetic sensor for locating land mines
An acousto-electromagnetic sensor for locating land mines Waymond R. Scott, Jr. a, Chistoph Schroeder a and James S. Martin b a School of Electrical and Computer Engineering b School of Mechanical Engineering
More informationA SHEAR WAVE TRANSDUCER ARRAY FOR REAL-TIME IMAGING. R.L. Baer and G.S. Kino. Edward L. Ginzton Laboratory Stanford University Stanford, CA 94305
A SHEAR WAVE TRANSDUCER ARRAY FOR REAL-TIME IMAGING R.L. Baer and G.S. Kino Edward L. Ginzton Laboratory Stanford University Stanford, CA 94305 INTRODUCTION In this paper we describe a contacting shear
More informationMeasurement of phase velocity dispersion curves and group velocities in a plate using leaky Lamb waves
Measurement of phase velocity dispersion curves and group velocities in a plate using leaky Lamb waves NDE2002 predict. assure. improve. National Seminar of ISNT Chennai, 5. 7. 12. 2002 www.nde2002.org
More informationDesign of Infrared Wavelength-Selective Microbolometers using Planar Multimode Detectors
Design of Infrared Wavelength-Selective Microbolometers using Planar Multimode Detectors Sang-Wook Han and Dean P. Neikirk Microelectronics Research Center Department of Electrical and Computer Engineering
More informationFIRST MEASUREMENTS FROM A NEW BROADBAND VIBROTHERMOGRAPHY MEASUREMENT SYSTEM
FIRST MEASUREMENTS FROM A NEW BROADBAND VIBROTHERMOGRAPHY MEASUREMENT SYSTEM Stephen D. Holland 1 Center for NDE and Aerospace Eng Dept, Iowa State Univ, Ames, Iowa 50011 ABSTRACT. We report on the construction
More informationOPTIMIZATION OF A PORTABLE MICROWAVE INTERFERENCE SCANNING SYSTEM FOR NONDESTRUCTIVE TESTING OF MULTI-LAYERED DIELECTRIC MATERIALS
OPTIMIZATION OF A PORTABLE MICROWAVE INTERFERENCE SCANNING SYSTEM FOR NONDESTRUCTIVE TESTING OF MULTI-LAYERED DIELECTRIC MATERIALS K. F. Schmidt,*, J. R. Little Evisive, Inc. Baton Rouge, Louisiana 70808
More informationAPPLICATION OF SWEPT FREQUENCY MEASUREMENTS TO THE EMBEDDED MODULATED SCATTERER TECHNIQUE
ICONIC 2007 St. Louis, MO, USA June 27-29, 2007 APPLICATION OF SWEPT FREQUENCY MEASUREMENTS TO THE EMBEDDED MODULATED SCATTERER TECHNIQUE Kristen M. Muñoz and Reza Zoughi Department of Electrical and Computer
More informationSources classification
Sources classification Radiometry relates to the measurement of the energy radiated by one or more sources in any region of the electromagnetic spectrum. As an antenna, a source, whose largest dimension
More informationQ-switched resonantly diode-pumped Er:YAG laser
Q-switched resonantly diode-pumped Er:YAG laser Igor Kudryashov a) and Alexei Katsnelson Princeton Lightwave Inc., 2555 US Route 130, Cranbury, New Jersey, 08512 ABSTRACT In this work, resonant diode pumping
More informationG. Hughes Department of Mechanical Engineering University College London Torrington Place London, WClE 7JE, United Kingdom
LEAKY RAYLEIGH WAVE INSPECTION UNDER SURFACE LAYERS G. Hughes Department of Mechanical Engineering University College London Torrington Place London, WClE 7JE, United Kingdom L.J. Bond Department of Mechanical
More informationInfluence of dielectric substrate on the responsivity of microstrip dipole-antenna-coupled infrared microbolometers
Influence of dielectric substrate on the responsivity of microstrip dipole-antenna-coupled infrared microbolometers Iulian Codreanu and Glenn D. Boreman We report on the influence of the dielectric substrate
More informationUSE OF GUIDED WAVES FOR DETECTION OF INTERIOR FLAWS IN LAYERED
USE OF GUIDED WAVES FOR DETECTION OF INTERIOR FLAWS IN LAYERED MATERIALS Gordon G. Krauss Julie Chen Paul E. Barbone Department of Aerospace and Mechanical Engineering Boston University Boston, MA 02215
More informationUltrasound- Lockin-Thermography for Advanced Depth Resolved Defect Selective Imaging
ECNDT 2006 - We.3.8.2 Ultrasound- Lockin-Thermography for Advanced Depth Resolved Defect Selective Imaging A. GLEITER, G. RIEGERT, TH. ZWESCHPER, G. BUSSE, Institute for Polymer Testing and Polymer Science
More informationCorrosion Steel Inspection under Steel Plate Using Pulsed Eddy Current Testing
4th International Symposium on NDT in Aerospace 2012 - Poster 4 Corrosion Steel Inspection under Steel Plate Using Pulsed Eddy Current Testing D.M. SUH *, K.S. JANG **, J.E. JANG **, D.H. LEE ** * Raynar
More informationA Laser-Based Thin-Film Growth Monitor
TECHNOLOGY by Charles Taylor, Darryl Barlett, Eric Chason, and Jerry Floro A Laser-Based Thin-Film Growth Monitor The Multi-beam Optical Sensor (MOS) was developed jointly by k-space Associates (Ann Arbor,
More informationLOS 1 LASER OPTICS SET
LOS 1 LASER OPTICS SET Contents 1 Introduction 3 2 Light interference 5 2.1 Light interference on a thin glass plate 6 2.2 Michelson s interferometer 7 3 Light diffraction 13 3.1 Light diffraction on a
More informationEMG4066:Antennas and Propagation Exp 1:ANTENNAS MMU:FOE. To study the radiation pattern characteristics of various types of antennas.
OBJECTIVES To study the radiation pattern characteristics of various types of antennas. APPARATUS Microwave Source Rotating Antenna Platform Measurement Interface Transmitting Horn Antenna Dipole and Yagi
More informationFundamentals of Electromagnetics With Engineering Applications by Stuart M. Wentworth Copyright 2005 by John Wiley & Sons. All rights reserved.
Figure 7-1 (p. 339) Non-TEM mmode waveguide structures include (a) rectangular waveguide, (b) circular waveguide., (c) dielectric slab waveguide, and (d) fiber optic waveguide. Figure 7-2 (p. 340) Cross
More informationDual-frequency Characterization of Bending Loss in Hollow Flexible Terahertz Waveguides
Dual-frequency Characterization of Bending Loss in Hollow Flexible Terahertz Waveguides Pallavi Doradla a,b, and Robert H. Giles a,b a Submillimeter Wave Technology Laboratory, University of Massachusetts
More informationModule 5: Experimental Modal Analysis for SHM Lecture 36: Laser doppler vibrometry. The Lecture Contains: Laser Doppler Vibrometry
The Lecture Contains: Laser Doppler Vibrometry Basics of Laser Doppler Vibrometry Components of the LDV system Working with the LDV system file:///d /neha%20backup%20courses%2019-09-2011/structural_health/lecture36/36_1.html
More information2x2 QUASI-OPTICAL POWER COMBINER ARRAY AT 20 GHz
Third International Symposium on Space Terahertz Technology Page 37 2x2 QUASI-OPTICAL POWER COMBINER ARRAY AT 20 GHz Shigeo Kawasaki and Tatsuo Itoh Department of Electrical Engineering University of California
More informationMAGNETO-DIELECTRIC COMPOSITES WITH FREQUENCY SELECTIVE SURFACE LAYERS
MAGNETO-DIELECTRIC COMPOSITES WITH FREQUENCY SELECTIVE SURFACE LAYERS M. Hawley 1, S. Farhat 1, B. Shanker 2, L. Kempel 2 1 Dept. of Chemical Engineering and Materials Science, Michigan State University;
More informationDAMAGE DETECTION IN PLATE STRUCTURES USING SPARSE ULTRASONIC TRANSDUCER ARRAYS AND ACOUSTIC WAVEFIELD IMAGING
DAMAGE DETECTION IN PLATE STRUCTURES USING SPARSE ULTRASONIC TRANSDUCER ARRAYS AND ACOUSTIC WAVEFIELD IMAGING T. E. Michaels 1,,J.E.Michaels 1,B.Mi 1 and M. Ruzzene 1 School of Electrical and Computer
More informationProceedings of Meetings on Acoustics
Proceedings of Meetings on Acoustics Volume 19, 2013 http://acousticalsociety.org/ ICA 2013 Montreal Montreal, Canada 2-7 June 2013 Signal Processing in Acoustics Session 1pSPa: Nearfield Acoustical Holography
More information/01/$ IEEE
EEE nstrumentation and Measurement Technology Conference Budapest, Hungary, May 21-23,21. A Method for Evaluating the Dielectric Properties of Composites Using a Combined Embedded Modulated Scattering
More information3D MICROWAVE IMAGING TECHNOLOGY USING ANTENNA ARRAY FOR DAMAGE ASSESSMENT OF CONCRETE STRUCTURE
16th ASCE Engineering Mechanics Conference July 16-18, 23, University of Washington, Seattle 3D MICROWAVE IMAGING TECHNOLOGY USING ANTENNA ARRAY FOR DAMAGE ASSESSMENT OF CONCRETE STRUCTURE Yoo Jin Kim
More informationMICROWAVE AND RADAR LAB (EE-322-F) LAB MANUAL VI SEMESTER
1 MICROWAVE AND RADAR LAB (EE-322-F) MICROWAVE AND RADAR LAB (EE-322-F) LAB MANUAL VI SEMESTER RAO PAHALD SINGH GROUP OF INSTITUTIONS BALANA(MOHINDERGARH)123029 Department Of Electronics and Communication
More informationPulsed Thermography and Laser Shearography for Damage Growth Monitoring
International Workshop SMART MATERIALS, STRUCTURES & NDT in AEROSPACE Conference NDT in Canada 2011 2-4 November 2011, Montreal, Quebec, Canada Pulsed Thermography and Laser Shearography for Damage Growth
More informationAN ACTIVELY-STABILIZED FIBER-OPTIC INTERFEROMETER FOR
AN ACTIVELY-STABILIZED FIBER-OPTIC INTERFEROMETER FOR LASER-ULTRASONIC FLAW DETECTION S.G. Pierce, R.E. Corbett*, and RJ. Dewhurst Department of Instrumentation and Analytical Science UMIST P.O. Box 88
More informationDesign of a Piezoelectric-based Structural Health Monitoring System for Damage Detection in Composite Materials
Design of a Piezoelectric-based Structural Health Monitoring System for Damage Detection in Composite Materials Seth S. Kessler S. Mark Spearing Technology Laboratory for Advanced Composites Department
More informationExposure schedule for multiplexing holograms in photopolymer films
Exposure schedule for multiplexing holograms in photopolymer films Allen Pu, MEMBER SPIE Kevin Curtis,* MEMBER SPIE Demetri Psaltis, MEMBER SPIE California Institute of Technology 136-93 Caltech Pasadena,
More informationAcoustic Yagi Uda Antenna Using Resonance Tubes
Acoustic Yagi Uda Antenna Using Resonance Tubes Yuki TAMURA 1 ; Kohei YATABE 2 ; Yasuhiro OUCHI 3 ; Yasuhiro OIKAWA 4 ; Yoshio YAMASAKI 5 1 5 Waseda University, Japan ABSTRACT A Yagi Uda antenna gets high
More informationNovel Probes and Evaluation Procedures to Assess Field Magnitude and Polarization
240 IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 42, NO. 2, MAY 2000 Novel Probes and Evaluation Procedures to Assess Field Magnitude and Polarization Katja Poković, Thomas Schmid, Jürg Fröhlich,
More informationSUPPLEMENTARY INFORMATION
SUPPLEMENTARY INFORMATION DOI: 10.1038/NNANO.2015.137 Controlled steering of Cherenkov surface plasmon wakes with a one-dimensional metamaterial Patrice Genevet *, Daniel Wintz *, Antonio Ambrosio *, Alan
More informationA NOVEL HIGH SPEED, HIGH RESOLUTION, ULTRASOUND IMAGING SYSTEM
A NOVEL HIGH SPEED, HIGH RESOLUTION, ULTRASOUND IMAGING SYSTEM OVERVIEW Marvin Lasser Imperium, Inc. Rockville, Maryland 20850 We are reporting on the capability of our novel ultrasonic imaging camera
More informationUNIVERSITI MALAYSIA PERLIS
UNIVERSITI MALAYSIA PERLIS SCHOOL OF COMPUTER & COMMUNICATIONS ENGINEERING EKT 341 LABORATORY MODULE LAB 2 Antenna Characteristic 1 Measurement of Radiation Pattern, Gain, VSWR, input impedance and reflection
More information6 Electromagnetic Field Distribution Measurements using an Optically Scanning Probe System
6 Electromagnetic Field Distribution Measurements using an Optically Scanning Probe System TAKAHASHI Masanori, OTA Hiroyasu, and ARAI Ken Ichi An optically scanning electromagnetic field probe system consisting
More informationRF simulations with COMSOL
RF simulations with COMSOL ICPS 217 Politecnico di Torino Aug. 1 th, 217 Gabriele Rosati gabriele.rosati@comsol.com 3 37.93.8 Copyright 217 COMSOL. Any of the images, text, and equations here may be copied
More informationComposite Thermal Damage Measurement with Handheld FTIR. April 9, 2013 Brian D. Flinn, Ashley Tracey, and Tucker Howie University of Washington
Composite Thermal Damage Measurement with Handheld FTIR April 9, 2013 Brian D. Flinn, Ashley Tracey, and Tucker Howie University of Washington Composite Thermal Damage Measurement with Handheld FTIR Motivation
More informationImplementation of Transient Eddy Currents from Lab Bench to the Production Environment
Implementation of Transient Eddy Currents from Lab Bench to the Production Environment Jesse A. Skramstad, NDT Solutions, Inc. Robert A Smith, QinetiQ Ltd UK Lt Gary Steffes and Charles Buynak, USAF, AFRL,
More informationInP-based Waveguide Photodetector with Integrated Photon Multiplication
InP-based Waveguide Photodetector with Integrated Photon Multiplication D.Pasquariello,J.Piprek,D.Lasaosa,andJ.E.Bowers Electrical and Computer Engineering Department University of California, Santa Barbara,
More informationMaterial analysis by infrared mapping: A case study using a multilayer
Material analysis by infrared mapping: A case study using a multilayer paint sample Application Note Author Dr. Jonah Kirkwood, Dr. John Wilson and Dr. Mustafa Kansiz Agilent Technologies, Inc. Introduction
More informationAPPLIED ELECTROMAGNETICS: EARLY TRANSMISSION LINES APPROACH
APPLIED ELECTROMAGNETICS: EARLY TRANSMISSION LINES APPROACH STUART M. WENTWORTH Auburn University IICENTBN Nlfll 1807; WILEY 2 OO 7 ; Ttt^TlLtftiTTu CONTENTS CHAPTER1 Introduction 1 1.1 1.2 1.3 1.4 1.5
More information